Blood cultures in the evaluation of uncomplicated skin and soft tissue infections.

Background: Blood cultures are often obtained in children hospitalized with skin and soft tissue infections (SSTIs). Because little evidence exists to validate this practice, we examined the yield of blood cultures in the evaluation of immunocompetent children with SSTIs.

Methods: Medical records were reviewed for all children admitted between January 1, 2007 and December 31, 2009 after emergency department evaluation and diagnosis of cellulitis or abscess. We compared patients with SSTIs (n = 482) with those with complicated SSTIs (cSSTIs; n = 98). A cSSTI was defined as surgical or traumatic wound infection, need for surgical intervention, or infected ulcers or burns. The SSTI group included patients without complicating factors.

Results: None of the patients in the SSTI group had a positive blood culture. In the cSSTI group, 12.5% of blood cultures were positive. The mean length of hospital stay (LOHS) of children with SSTIs was shorter than that of those with cSSTIs (P < .001). In the SSTI group, obtaining a blood culture was associated with a higher mean LOHS (P = .044).

Conclusions: Blood cultures are not useful in evaluating immunocompetent children who are admitted to the hospital with uncomplicated SSTIs, and they are associated with a nearly 1-day increase in mean LOHS.